Building Construction Memory Capsule


🔸 A stair is a set of steps leading from one floor to the other

🔸 The room or enclosure of the building, in which the stair is located is known as staircase

🔸 The opening occupied by the stair is known as stairway


1. Step : It is a portion of stair which permits ascent or descent. It is comprised of a tread and a riser. A stair is composed of a set of steps. 

2. Tread: It is the upper horizontal portion of a step upon which the foot is placed while ascending or descending. 

3. Riser: It is the vertical portion of a step providing support to the tread.

4. Flight: This is defined as an unbroken series of steps between landings. 

5. Landing: It is the level platform at the top or bottom of a flight between the floors. A landing facilitates a change of direction and provides an opportunity for taking a rest during the use of the stair. 

6. Rise: It is the vertical distance between two successive tread faces.

7. Going: It is the horizontal distance between two successive riser faces.

8. Nosing: It is the projecting part of the tread beyond the face of the riser. It is usually rounded off from architectural considerations. 

9. Scotia: It is a moulding provided under the nosing to improve the elevation of the step, and to provide strength to the nosing. 

10. Soffit : It is the underside of a stair. 

11. Line of nosings : It is an imaginary line parallel to the strings and tangential to the nosings.

12. Pitch or slope : It is the angle which the line of nosing of the stair makes with the horizontal. 

13. Strings or stringers : These are the sloping members which supports the steps in a stair. They run along the slope of the stair.

14. Newel post : Newel post is a vertical member which is placed at the end of flights to connect the ends of strings and hand rail.

15. Baluster : It is vertical member of wood or metal, supporting the handrail. 

16. Balustrade : It consists of a row of balusters surmounted by a handrail to provide protection for the users of the stair.

17. Hand Rail : It is a rounded or moulded member of wood or metal following generally the contour of the nosing line, and fixed on the top of balusters

18. Head Room : It is the minimum clear vertical distance between and overhead structure (i.e., ceiling etc.). 

19. Run : It is the total length of stairs in a horizontal plane, including landing

♦️ Requirement of Good stair

🔸 Width of stair

👉 In domestic building a 90cm wide stair is sufficient.

👉 In public building 1.5m to 1.8m width may be required.

🔸 Length of flight

👉 The number of steps are not more than 12 and not less than 3

🔸 Pitch of stair

👉 Pitch should be limited to 30° to 45°

🔸 Head room

👉 It should not be less than 2.1 to 2.3m

🔸 Step dimensions

👉 Going :- The going should not be less than 25cm. 30cm going is quite comfortable

👉 Rise :- Rise should be between 10cm to 15cm

👉 Width of landing should not be less than the width of stair.


♦️ Dimensions of stairs

The following thumb rules are followed ( all dimensions are in cm )

1. (2 × Rise) + Going = 60

2. Rise + Going = 40 to 60

3. Rise × Going = 400 to 450

4. Adopt Rise = 14cm and Going = 30cm as standard


🔸 A roof may be defined as the uppermost part of a building, provided as a structural covering to protect the building from weather.

♦️ Types of roof

1. Pitched or sloping roof : Pitched roof is the one which slope of roof more than 10°

2. Flat roofs or terraced roofs : Flat roof is the one which is either horizontal or practically horizontal with slope less than 10°

3. Curved roofs


🔸 English bond:- Alternate Course of Headers and Stretchers. It is strongest bond.

🔸 Flemish bond:- Each Course consists of Alternate Header and Stretcher.

🔹 Herring-bone Bond: Commonly used for Brick Paving.

🔹 Stretcher Bond :- It is preferred when walls of Half brick thickness need to be constructed.

🔸 Rat-trap bond:- Bond in which cavity is existing.

In this method,bricks are placed in vertical position instead of conventional horizontal position and thus creating a wall(hollow space) within the wall.

🔸 King Closer :- Rectangular brick whose one end has been cut off diagonally to half the width of brick

🔸 Queen Closer :- When Brick is cut along it's length,making it two halves then it is called Queen Closer.

🔸 Brick bat:- Cut portion of brick

🔸 Prepend :- Vertical joint in bricks

🔹 Silica in Brick :- enables brick to retain it's shape.

🔹 Alumina in Brick: Responsible for plasticity characteristics of brick earth.

🔹 Excess silica in Brick:-makes brick brittle and weak.

🔹 Excess Alumina in Brick:- Produce crack during drying and burning

🔹 Excess of Magnesia in Brick :- Affects colour and makes brick yellow.

🔹 Excess of lime in Brick :-

Causes brick to melt and loss it's shape.

🔹 Excess Iron oxide in Brick:-

Makes brick to dark blue.


1)To check Setting Time Apparatus used:- 

👉Use Vicat Apparatus:-

~Initial Setting Time Test:- Square Needle(1mm)

👉 Final Setting Time Test:- Annular Collar(5mm)

👉 Percentage of Water For:-

Setting Time Test:-0.85P

Soundness Test:-0.78P

2) Specific Gravity

Le-chateliers flask used.

Sp.G of Cement is 3.15.

3)Consistency Test Of Cement

Vicat Plunger is used.


4)Fineness Test of Cement

Seive Analysis & Blaine's Air Permeability Test.


5)Soundness Test

Le-chatelier's Test(Lime)


Autoclave Test (Lime & Magnesia)


6) Tensile Strength Test

Std.Briquette Apparatus.


Tricalcium Aluminate(C3A) is a compound in Cement which is quickest to react with Water.


👉 Gypsum(CaSO4) :- Retarder.


👉 Calcium Chloride(CaCL2) : Accelerator.


👉 Ultimate Strength:- Dicalcium Silicate.


👉 Early Strength:- Tricalcium Silicate.


👉 Early Setting:- Tricalcium Aluminate


👉 For Underwater Construction:-

Use Quick Set Cement.


👉 To get Low Heat Cement:-

Reduce Tricalcium Silicate(C3S)


Pitched Roof


♦️ Forms of pitched roof


1. Lean to roof : This type of roof which slope in one direction


2. Gable roof :- This type of roof which slope in Two direction


3. Hip roof : This type of roof which slope in four direction


4. Gambrel roof :- This type of roof which slope in two direction but there is break in each slope


5. Mansard roof : This type of roof which slope in four direction but each slope has break


6. Deck roof :- This type of roof which slope in four direction but plane surface is formed at top.


Basic elements of pitched roof


1. Span : It is the clear distance between the supports of an arch, beam or roof truss.


2. Rise : It is the vertical distance between the top of the ridge and the wall plate 


3. Pitch : It is the inclination of the sides of a roof to the horizontal plane. 


4. Ridge : It is defined as the apex line of the sloping roof.


5. Eaves : The lower edge of the inclined surfaces is called eaves. From eaves, the rain water from the roof surface drops down


6. Hip : It is the ridge formed by the intersection of two sloping surfaces, where exterior angle is greater than 180°


7. Valley : It is a reverse of a hip. It is formed by the intersection of two roof Surfaces, making an external angle less than 180°. 


8. Hipped end : It is the sloped triangular surface formed at the end of a roof.


9. Verge : The edge of a gable, running between the eaves and ridge, is known as a verge. 


10. Ridge piece or ridge beam or ridge board : It is the horizontal wooden member, in the form of a beam or board, which is provided at the apex of a roof truss. It supports the common rafters fixed to it. 


11. Common rafters or Spars : These are inclined wooden members running from the ridge to the eaves. Depending upon the roof covering material, the rafters are Spaced 30 to 45 cm centre to centre. 


12. Purlins : These are horizontal wooden or steel members, used to support common rafters of a roof when span is large. Purlins are supported on trusses or walls.


13. Hip rafters : These are the sloping rafters which form the hip of a sloped roof


14. Battens : These are thin strips of wood, called scantling, which are nailed to the rafters for lying roof materials above.


15. Boardings : They act Similar to battens and are nailed to common rafter to support roofing material.


16. Template : This Is a square or rectangular block of stone or concrete placed under a beam or truss, to spread the load over a larger area of the wall. 


17. Cleats : These are short sections of wood or steel (angle iron), which are fixed on the principal rafters of trusses to support the purlins.


18. Truss : A roof truss is a frame work, usually of triangles, designed to support the roof covering or ceiling over rooms.


🔴 Types of pitched roof & suitable span


1. Single roof


🔸 Lean to roof : upto 2.40 m


🔸 Couple roof : upto 3.6 m


🔸 Couple close roof : upto 4.2 m


🔸 Collar beam roof : upto 4.2 m


2. Double roofs : upto 4.8 m


3. Trussed roof


🔹 King post truss : 5-8 m


🔹 Queen post truss : 8-12 m


🔹 Steel trusses : for span >12 m




🔸 A door may be defined as an openable barrier secured in a wall opening.


🔸 Technical Terms


1. Frame : It is an assembly of horizontal and vertical members, forming an enclosure, to which the shutters are fixed. 


2. Shutters : These are the openable parts of a door or window. It is an assembly of styles, panels and rails. 


3. Head : This is the top or uppermost horizontal part of a frame. 


4. Sill : This is the lowermost or bottom horizontal part of a window frame. Sills are normally not provided in door frames. 


5. Horn : These are the horizontal projections of the head and sill of a frame to facilitate the fixing of the frame on the wall opening. The length of horns is kept about 10 to 15 cm


6. Style : Style is the vertical outside member of the shutter of a door or window. 


7. Top rail : This is the top most horizontal member of a shutter. 


8. Lock rail : This is the middle horizontal member of a door shutter, to which locking arrangement is fixed.


9. Bottom rail : This is the lowermost horizontal member of a shutter.


10. Intermediate or cross-rails : These are additional horizontal rails, fixed between be top and bottom rails of a shutter. A rail fixed between the top rail and lock rail is called frieze rail. 


11. Panel : This is the area of shutter enclosed between the adjacent rails. 


12. Mullion : This is a vertical member of a frame, which is employed to sub-divide a Window or a door vertically.


13. Transom : This is a horizontal member of a frame, which is employed to sub divide a window opening horizontally. 


14. Hold fasts : These are mild steel flats (section 30 mm x 6 mm), generally bent into Z-shape, to fix or hold the frame to the opening. The horizontal length of hold fast is kept about 20 cm, and is embedded in the masonry. 


15. Jamb : This is the vertical wall face of an opening which supports the frame. 


16. Reveal : It is the external jamb of a door or window opening at right angles to the wall face. 


17. Rebate : It is depression or recess made inside the door frame, to receive the door shutter.




♦️ Size of doors


🔹 Common width height relation used in India


👉 Width :- 0.4 to 0.6 heights


👉 Height :- (width + 1.2 ) meter



🔸 Designation of door


👉 8DS20 means width (800mm), Height (2000mm), D (Door) & S (Single shutter)


👉 10DT21 means width (1000mm), Height (2100mm), D (Door) & T (Double shutter)




🔸 Window is vented barrier secured in wall opening


🔸 Following thumb rule used for window


👉 Width of window :- (width of room + height of room)/8


👉 The total area of window opening - 10% to 20% of floor area of the room


👉 The area of window opening should be atleast one square metre for every 30 to 40 cubic metre of inside content of the room.


👉 In public building, Minimum area of windows - 20% of floor area


👉 For sufficient natural light, the area of glazed panels should atleast be 8 to 10% of the floor area


🔸 Bay window :- Bay window projected outside the external wall of the room. 


🔸 Clere storey window : These windows are provided in a room which has greater ceiling height than the surrounding rooms or when a lean to roof of low height is there adjacent to the room.


🔸 Dormer window :- A dormer window is a vertical window provided on the sloping roof




🔸 Formwork is a temporary ancillary construction used as a mould for the structure, in which concrete is placed and in which it hardens and matures.


🔸 The cost of formwork may be up to 20℅ to 25℅ of the cost of structure


🔸 The operation removing the formwork is commonly known as stripping


♦️ Stripping time for different components


👉 Walls, columns and vertical sides of beam : 24 to 48hr


👉 Slab soffits (Props left under) : 3 days


👉 Beam soffits (props left under) : 7 days


👉 Removal of props to slab :


1. Spanning upto 4.5m : 7days


2. Spanning over 4.5m : 14days


👉 Removal of props to beam and arches :


1. Spanning upto 6m : 14days


2. Spanning over 6m : 21days


Thermal insulation


🔸 Thermal insulation is used to indicate the construction or provisions by way of which transmission of heat from or in the room is retarded.


♦️ Heat transfer


1. Conduction : It is direct transmission of heat through a material.


2. Convection : Heat is transmitted by convection in fluids and gases as a result of circulation.


3. Radiation : Heat transferred by radiation through space in the form of radiant energy.


Thermal Insulation


♦️ Technical terms


👉 Thermal conductivity (k) : The thermal conductivity of a material is the amount of heat that will flow through an unit area of material, of unit thickness in one hour, when the Difference of two temperatures is maintained at 1°C.


👉 Thermal resistivity (l/k) : This is the reciprocal of thermal conductivity and is denoted by 1/ k. 


👉 Thermal conductance (c) : It is the thermal transmission of a single layer structure per unit areadivided by temperature difference between the hot and cold faces.


👉 Thermal resistance (R) : It is the reciprocal of thermal conductance. {R = L/k}

Where, L is thickness


👉 Surface coefficient (f) : It is the thermal transmission by convection, conduction or radiation from unit area of the surface, for unit temperature difference between surface and surrounding medium.


👉 Surface resistance (1/f) : It is the reciprocal of surface coefficient


👉 Total thermal resistance (RT) : The total thermal resistance is the sum of the surface resistances and the thermal resistance of the building unit itself. 


👉 Thermal transmittance (U) : Thermal transmittance is the thermal transmission through unit area of the given building divided by the temperature difference between the air or other fluid on either side of the building unit in steady state condition.


👉 Thermal damping (D) : It is dependent on thermal resistance. {D = 100*(To - Ti)/To}

Where, To is outside temperature

Ti is inside temperature


👉 Thermal time constant (T) : It is the ratio of heat stored to thermal transmittance of the structure. {T = Q/U}




🔸 It is science of sound which deals with origin, propagation and auditory sensention of sound and also with design and construction of different building unit is set optimum conditions for producing and listening speech, music etc.


🔸 Characteristics of audible sound


👉 The velocity of sound in atmospheric air at 20℃ is 343 m/sec


👉 The velocity of sound in pure water is 1450 m/sec


👉 The velocity of sound in bricks is 4300 m/sec


👉 The velocity of sound in concrete is 4000 m/sec


🔸 Intensity of sound : It is defined as the amount or flow of wave energy crossing per unit time through a unit area taken perpendicular to the direction of propagation.


🔸 Webler & Fechners law : It states that the magnitude of any sensation is proportional to the logarithm of the physical stimulus that produces it. {L ∞ logI}

So, L = klog(I/Io)




👉 Frequency or pitch : It is defined as the number of cycles which sounding body makes in each unit of time.


🔸 Defects due to reflected sound


👉 Echoes : An echo is produced when the reflected sound wave reaches the ear just when the original sound from the same source has been already heard.


👉 Reverberation : It has been generally noticed that in public halls and auditorium the sound persists even after the source of sound has ceased. This persistence of sound is called reverberation. 



♦️ Reverberation time and acoustical quality


👉 0.5 to 1.50 sec - Excellent


👉 1.50 to 2 sec - Good


👉 2 to 3 sec - Fairly good


👉 3 to 5 sec - Bad


👉 Above 5 sec - Very bad


♦️ Optimum reverberation time


👉 Cinema theatres : 1.3


👉 Churches : 1.8 to 3


👉 Law courts, committee room, conference hall : 1 to 1.5


👉 Large hall : 2 to 3


👉 Music concert hall : 1.6 to 2


👉 Parliament house, Assembly hall, Council chamber : 1 to 1.5


👉 Public lecture hall : 1.5 to 2


Plumbing services


🔸 The services like water supply, drainage, sanitation etc. are sometimes known as plumbing services.


♦️ Pipes


🔸 Soil pipe : A soil pipe is a pipe through which human excreta flows


🔸 Waste pipe : It is a pipe which carries only the liquid waste. It does not carry human excreta.


🔸 Vent pipe : It is pipe which is provided for the purpose of the ventilation of the system. It facilitate exit of foul gases


🔸 Rain water pipe : It is pipe which carries only rain water.


🔸 Anti siphonage pipe : It is pipe which is installed in the house drainage to preserve the water seal of traps.


🔸 The following sizes of pipe are commonly used in house drainage


👉 Soil pipe : 100mm


👉 Waste pipe (Horizontal) : 30 to 50 mm


👉 Waste pipe (Vertical) : 75 mm


👉 Rain water pipe : 75 mm


👉 Vent pipe : 50 mm


👉 Anti siphonage pipe


1. Connected with soil pipe : 50mm


2. Connecting waste pipe : 40mm


♦️ Traps


🔸 A traps is a depressed or bent fitting which, when provided in a drainage system always remains full of water, thus maintaining q water seal


🔸 The depth of water seal varies from 25 to 75 mm


🔸 Classification of traps


1. According to shape


👉 P trap


👉 Q trap or half s trap


👉 S trap


2. According to use


👉 Floor trap or nahni trap : It is used to collect wash water from floors, kitchen and rooms.


👉 Gully trap : It is used to disconnect sullage drain from main drainage system


👉 Intercepting traps : It is provided at the junction of house drain with the public sewer or septic tank.

Plumbing services

♦️ systems of plumbing

🔸 Single stack system

👉 This is the simplest in which the waste matter from baths, sinks as well as foul matter from WC. are discharged in one single pipe is called Soil & waste pipe (SWP)

🔸 One pipe system

👉 In this system a separate vent pipe is provided.

👉 The system is costlier than the single stack system

🔸 Single stack system partially ventilated 

👉 This is modified from of the single stack system and one pipe system.

👉 In this system the waste from WC, sinks etc. is discharged into one common SWP

🔸 Two pipe system

👉 In this system separate soil pipe and waste pipe are provided

♦️ Principles of building planning

1. Aspect : It is defined as the positioning of windows and doors in the external walls to take maximum advantage of natural gifts such as sunlight and wind or breeze.

2. Prospect : Prospect means taking advantage of desirable views available from Windows, doors and balconies of features outside the building auch as gardens, lake, sea, river etc.

3. Orientation : Orientation means the placement of rooms with reference to the north direction.

4. Privacy

5. Circulation : Circulation refers to movement from one place to other inside the building

6. Grouping : This means planning room with same or similar functions together as a group.

7. Roominess : A psychological feeling about bigness or smallness of space of a room is called roominess.

8. Furniture requirements

9. Sanitation : Sanitation is concerned with light & ventilation. It includes proper planning for drainage arrangements.

10. Elegance : It refers to the elevation of the building. The front elevation of the building must be aesthetically pleasing & elegant.

11. Economy : Planning of building should be economical

12. Access : The principle of access stresses the need for ease in moving from room to room.

13. Architectural composition : This principle deals with the aesthetics or the beauty of the building. Architectural concepts such as unity, contrast, scale, proportion, mass composition are taken into account.

14. Climate and it's affect : The climate of a place also affect the planning of a building.


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